1. Field of the Invention
The present invention generally relates to devices for covering or enclosing elongate rail structures. More particularly, the invention is directed to a cover for enclosing and protecting metallic highway guardrails from physical deterioration, while simultaneously enhancing their external appearance and visibility.
2. Description of the Prior Art
Guardrail assemblies presently known and installed along highways typically comprise at least one horizontal guardrail section that is supported at spaced locations by a plurality of vertical posts anchored in the ground. Each guardrail section includes a plurality of individual guardrails joined in an end-to-end relationship, with each guardrail being generally in the form of a steel channel having a somewhat corrugated configuration that imparts rigidity and strength thereto. The guardrail section is fastened to the vertical posts by bolting, riveting or similar fastening expedient.
Metallic guardrails made of steel are subject to rapid deterioration through corrosion from constant exposure to rain and moisture. The problem of corrosion is further aggravated from the presence of salt which is normally deposited on the highways during wintertime. Attempts at preventing deterioration of guardrails through corrosion have generally been centered upon providing galvanized coatings of zinc over the exposed steel surfaces of the guardrails. While this expedient does provide some degree of protection against corrosion, it is vulnerable to attack by mechanical abrasion, such as caused by stones and other debris thrown against the guardrails by passing vehicles or high winds. These mechanical forces serve to damage and erode away the galvanized coatings on the guardrails, thereby permitting corrosion to rapidly occur at the exposed steel areas. The physical deterioration of guardrails through corrosion imparts an unsightly appearance to the guardrail assembly that is both time consuming and expensive to repair.
The prior art has taught that guardrail structures may be provided with covers for a variety of reasons, including enhancing external appearance and prevention of injury and damage through contact with the rail by a person or object. Such known covers, particularly when utilized in conjunction with large rail structures, normally require the use of adhesives or mechanical fasteners in order to assure a secure attachment to the rail structure. This situation has also proved to be both time consuming and costly when long lengths of guardrail sections must be covered.